1. Field of the Invention
This invention relates to a guidance control system for the discipline of a traction vehicle along a prescribed path.
2. Description of the Prior Art
It is known in the prior art to control a vehicle so that it follows a path defined by a current carrying guide wire laid in or on the surface over which the vehicle travels. Examples of such systems are found in U.S. Pat. No. 2,317,400 to C. L. Paulus et al, and in U.S. Pat. No. 3,498,403 to Kohls.
The present invention proposes a two way radio guidance control system in which a traction vehicle sends out location and destination intelligence to a wayside station or central controller which in turn transmits steering and traction intelligence to control the vehicle. The path to be followed by the vehicle is not a single guide wire, but segmented, closed loop antennae, arranged along and defining the path of travel. The guide path thus consists of segmented vertical loop antennae, each one called a BLOCK which is the basic intelligence unit. The vehicle is commanded to be displaced successively from BLOCK to BLOCK. The fact that a vehicle is transmitting destination information into a discrete BLOCK serves both to identify the location of the vehicle as well as convey the identity of its ultimate destination. Further, when the wayside station or central processor sends steering and traction commands to a discrete BLOCK, the radiated electromagnetic energy is confined to a relatively narrow region so that sensors mounted on the vehicle front wheel assembly, can detect deviations from the proximate vertical loop antenna with precision, and generate control signals to force the vehicle back to the guide path. The sending of traction signals to only one BLOCK at a time, insures that the wayside station or central processor has control of the vehicle at all times.